The present invention relates to vehicle bumper systems, and more particularly relates to a bumper system having an integrated energy absorber and beam, and also relates to novel beam constructions such as those that are shaped for engagement with mating energy absorbers.
Bumper systems using integrated energy absorber and bumper beam arrangements are desired to improve assembly of bumper systems to vehicles, to minimize the number and types of mechanical fasteners overall, and to simplify tooling. In particular, it is desirable to provide a design where the beam and energy absorber can be assembled off-line of the main vehicle assembly line into a unitary subassembly, and then manipulated as a unit for attachment to the vehicle. Also, it is desirable to attach fascia to the subassembly, and to integrate and attach other components to the subassembly, such as headlights, grilles, and other functional and ornamental components. At the same time, impact durability and enhanced energy absorption continue to be high priority items in bumper systems, and accordingly, any subassembly should preferably not detract from the same.
In addition to the above, many vehicle manufacturers and some insurance groups and government entities are pressing for improved crashworthiness of vehicles, and also for bumper systems that will provide for better pedestrian safety. Longer bumper strokes with lower initial energy absorption rates have the possibility of satisfying these desires, but this can result in energy absorbers that are physically larger in size than present bumper systems, and that are not easy to package and carry at a front of the vehicle. Thus, new integrated bumper systems are desired to deal with the conflicting functional and design requirements.
Improvements are also desired in rear bumper systems on vehicles. In particular, vehicle manufacturers are looking increasingly at energy absorbers for rear bumper systems that are not dissimilar in shape and function to energy absorbers for front bumper systems. However, the energy absorber of any such rear bumper system must be integrated into the bumper system such that it does not interfere with other functional and aesthetic requirements at a rear of the vehicle. For example, many rear bumper systems include a step, and/or are adapted to support a ball hitch for hauling a trailer.
Accordingly, bumper systems are desired solving the aforementioned problems and having the aforementioned advantages.